Makefile

BUILDDIR	:=	./build
SRC_BASE	:=	.

SOURCES := $(wildcard *.cpp)
TARGETS := $(patsubst %.cpp,$(BUILDDIR)/%/64/lin.xpl,$(SOURCES))
HINTFILE := $(HOME)/.x-plane/x-plane_install_11.txt
XP11INST := $(shell cat $(HINTFILE))

# You can symlink "SDK" to your SDK, otherwise this will be downloaded:
SDK_DOWNLOAD          := XPSDK301.zip
SDK_DOWNLOAD_URL      := http://developer.x-plane.com/wp-content/plugins/code-sample-generation/sample_templates/$(SDK_DOWNLOAD)
FILE_TO_PROMPT_SDK_DL := SDK/CHeaders/XPLM/XPLMPlugin.h

LIBS =

INCLUDES = \
	-I$(SRC_BASE)/SDK/CHeaders/XPLM \
	-I$(SRC_BASE)/SDK/CHeaders/Widgets

DEFINES = -DXPLM200=1 -DXPLM210=1 -DXPLM300=1 -DXPLM301=1 -DAPL=0 -DIBM=0 -DLIN=1

############################################################################


VPATH = $(SRC_BASE)

CSOURCES	:= $(filter %.c, $(SOURCES))
CXXSOURCES	:= $(filter %.cpp, $(SOURCES))

CDEPS64			:= $(patsubst %.c, $(BUILDDIR)/obj64/%.cdep, $(CSOURCES))
CXXDEPS64		:= $(patsubst %.cpp, $(BUILDDIR)/obj64/%.cppdep, $(CXXSOURCES))
COBJECTS64		:= $(patsubst %.c, $(BUILDDIR)/obj64/%.o, $(CSOURCES))
CXXOBJECTS64	:= $(patsubst %.cpp, $(BUILDDIR)/obj64/%.o, $(CXXSOURCES))
ALL_DEPS64		:= $(sort $(CDEPS64) $(CXXDEPS64))
ALL_OBJECTS64	:= $(sort $(COBJECTS64) $(CXXOBJECTS64))

CFLAGS := $(DEFINES) $(INCLUDES) -fPIC -fvisibility=hidden


# Phony directive tells make that these are "virtual" targets, even if a file named "clean" exists.
.PHONY: all clean
# Secondary tells make that the .o files are to be kept - they are secondary derivatives, not just
# temporary build products.
.SECONDARY: $(ALL_OBJECTS) $(ALL_OBJECTS64) $(ALL_DEPS)

all: $(TARGETS)

install: $(TARGETS)
	@if [ -f "$(XP11INST)/X-Plane-x86_64" ]; then \
	for p in $(patsubst %.cpp,%,$(SOURCES)); do mkdir -p "$(XP11INST)/Resources/plugins/$$p/64"; cp -v $(BUILDDIR)/$$p/64/lin.xpl "$(XP11INST)/Resources/plugins/$$p/64/"; done; \
	else echo "X-Plane 11 not detected, please write $(HINTFILE) or edit Makefile"; \
	fi


# Target rules - these just induce the right .xpl files.

$(BUILDDIR)/%/64/lin.xpl: $(BUILDDIR)/obj64/%.o
	@echo Linking $@
	mkdir -p $(dir $@)
	gcc -m64 -static-libgcc -shared -Wl,--version-script=exports.txt -o $@ $< $(LIBS)

# Compiler rules

# What does this do?  It creates a dependency file where the affected
# files are BOTH the .o itself and the cdep we will output.  The result
# goes in the cdep.  Thus:
# - if the .c itself is touched, we remake the .o and the cdep, as expected.
# - If any header file listed in the cdep turd is changed, rebuild the .o.
$(BUILDDIR)/obj64/%.o : %.c $(FILE_TO_PROMPT_SDK_DL)
	mkdir -p $(dir $@)
	g++ $(CFLAGS) -m64 -c $< -o $@
	g++ $(CFLAGS) -MM -MT $@ -o $(@:.o=.cdep) $<

$(BUILDDIR)/obj64/%.o : %.cpp $(FILE_TO_PROMPT_SDK_DL)
	mkdir -p $(dir $@)
	g++ $(CFLAGS) -m64 -c $< -o $@
	g++ $(CFLAGS) -MM -MT $@ -o $(@:.o=.cppdep) $<

clean:
	@echo Cleaning out everything.
	rm -rf $(BUILDDIR)

# Include any dependency turds, but don't error out if they don't exist.
# On the first build, every .c is dirty anyway.  On future builds, if the
# .c changes, it is rebuilt (as is its dep) so who cares if dependencies
# are stale.  If the .c is the same but a header has changed, this 
# declares the header to be changed.  If a primary header includes a 
# utility header and the primary header is changed, the dependency
# needs a rebuild because EVERY header is included.  And if the secondary
# header is changed, the primary header had it before (and is unchanged)
# so that is in the dependency file too.
-include $(ALL_DEPS64)


# Auto-download SDK
$(SDK_DOWNLOAD):
	wget $(SDK_DOWNLOAD_URL)

$(FILE_TO_PROMPT_SDK_DL): $(SDK_DOWNLOAD)
	unzip $<
	touch $@